Rail interoperability: National Technical Specification Notices (NTSNs)
UK railway technical standards, known as NTSNs, have replaced EU technical specifications for interoperability (TSIs).
National Technical Specification Notices (NTSNs) have been published by the Secretary of State for Transport pursuant to regulation 3B of the聽.
The first editions of the 11 NTSNs for Great Britain (GB) were published on 1 January 2021.
Following a substantial NTSN revision exercise, which was informed by an , we published updated editions of 7 NTSNs on 2 May 2025. They apply in GB only.
罢丑别听EU聽Technical Specifications for Interoperability (TSIs) continue to have direct effect in Northern Ireland.
罢丑别蝉别听NTSNs聽set standards to be complied with in relation to the design, construction, placing in service, upgrading, renewal, operation and maintenance of the parts of the rail system, as well as the professional qualifications and health and safety conditions of the staff who contribute to its operation and maintenance.
The 11 NTSNs replace the TSIs听蹿辞谤听GB. They are:
- Safety in Railway Tunnels (SRT)
- Control Command and Signalling (CCS)
- Operation and Traffic Management (OPE)
- Infrastructure (INF)
- Energy (ENE)
- Rolling Stock 鈥� Locomotive and Passenger (LOC and PAS)
- Rolling Stock 鈥� Noise (NOI)
- Rolling Stock 鈥� Freight Wagons (WAG)
- Accessibility (ACC) (formerly called Persons with Reduced Mobility (PRM))
- Telematics Applications for Passenger Services (TAP)
- Telematics Applications for Freight (TAF)
The Modules NTSN replaces and substantially reproduces requirements within聽聽on modules for the procedures for assessment of conformity, suitability for use and聽EC聽verification to be used in the technical specifications for interoperability.
The NTSN concerning the assessment of interoperability constituents against聽UK-specific cases, including the further assessment of interoperability constituents which hold an聽EC聽declaration of conformity or suitability for use, sets out the procedure that must be followed in accordance with聽.
The Department for Transport (DfT) worked with RSSB to create the NTSNs.